scholarly journals Freshwater mollusc diversity in the Kruger National Park: a comparison between a period of prolonged drought and a period of exceptionally high rainfall

Koedoe ◽  
2002 ◽  
Vol 45 (2) ◽  
Author(s):  
K.N. De Kock ◽  
C.T. Wolmarans ◽  
L.H. Du Preez
Keyword(s):  
Species Diversity ◽  
National Park ◽  
Freshwater Snail ◽  
Kruger National Park ◽  
Snail Species ◽  
High Rainfall ◽  
Freshwater Molluscs ◽  
Freshwater Mollusc ◽  
Prolonged Drought ◽  
Positive Effect

Most of the previous records of the freshwater molluscs from the Kruger National Park date back to 1966 and earlier. On account of several droughts between 1966 and 1995, a survey was done in 1995 to evaluate the effect of these droughts on the mollusc population. As a result of extensive rainfall between 1995 and 2000 another survey was conducted to establish the effect of a period of exceptionally high rainfall on the species’ diversity of the mollusc population. With the exception of three habitats, an increase in mollusc diversity was recorded for all the other habitats previously surveyed. One of the invader freshwater snail species, Aplexa marmorata, collected in only one habitat in 1995, was found in seven habitats located mainly in the south during the 2001 survey. Another interesting finding was that juvenile specimens of Lanistes ovum, of which large specimens were present prior to 1966 but none found in 1995, were present in the Sirheni Dam in 2001. From this study the positive effect of the high rainfall on the species’ diversity is highly evident.

scholarly journals A re-evaluation of the occurrence of freshwater molluscs in the Kruger National Park

Koedoe ◽  
1998 ◽  
Vol 41 (1) ◽  
Author(s):  
K.N. De Kock ◽  
C.T. Wolmarans
Keyword(s):  
Species Diversity ◽  
National Park ◽  
Kruger National Park ◽  
Intermediate Hosts ◽  
Freshwater Molluscs ◽  
Freshwater Mollusc ◽  
Mollusc Species ◽  
Trematode Parasites

Most of the previous records of the freshwater molluscs from the Kruger National Park date back prior to and up to 1966. On account of several droughts between 1966 and 1995 it was decided to do a survey of the freshwater mollusc population in 1995 to evaluate the effect of these droughts. The traditional mollusc intermediate hosts were also screened for trematode parasites to establish whether or not they were infected. No infected molluscs were found. Eight of the 19 species reported up to 1966 were not found during the 1995 survey. Three new mollusc species were collected in 1995. The consequences of the drought are clearly visible when the species diversity found in the dams in the 1995 survey, is compared to what was previously recorded.

scholarly journals The current status of freshwater molluscs in the Kruger National Park

Koedoe ◽  
2006 ◽  
Vol 49 (2) ◽  
Author(s):  
C.T. Wolmarans ◽  
K.N. De Kock
Keyword(s):  
Species Diversity ◽  
National Park ◽  
Kruger National Park ◽  
Current Status ◽  
Freshwater Molluscs ◽  
Freshwater Mollusc ◽  
Current Survey ◽  
Mollusc Species ◽  
Flow Through ◽  
Alien Invader

Surveys regarding the freshwater mollusc population of the Kruger National Park commenced before 1966 and was repeated in 1995, 2001 and recently in 2006. During this period the park was exposed to several droughts as well as floods, all of which could have had some influence on the various habitats in the park. Industrial developments and urbanisation near some of the major rivers outside the park, but which flow through the park, could also have a detrimental effect on the species diversity of the freshwater molluscs. The recent survey in 45 habitats included several dams and rivers. The survey was done to determine the current status of the mollusc species diversity. By comparing it with previous surveys, an attempt was made to establish the overall health of freshwater mollusc habitats. From the results it is clear that there was a drastic decrease in the mollusc species diversity in five of the habitats. Although there was a slight change in the species composition in some of the major rivers there was no difference in the number of species collected in these habitats. Tarebia granifera, an alien invader mollusc, was found in several rivers and dams. Gyraulus costulatus, Melanoides victoriae and Eupera ferruginea, which could not be found during the survey of 2001, were collected during the current survey.

scholarly journals Invasive alien freshwater snail species in the Kruger National Park, South Africa

Koedoe ◽  
2008 ◽  
Vol 50 (1) ◽  
Author(s):  
Kenné N. De Kock ◽  
Cornelius T. Wolmarans
Keyword(s):  
South Africa ◽  
Species Diversity ◽  
National Park ◽  
Negative Impact ◽  
Freshwater Snail ◽  
Kruger National Park ◽  
Water Bodies ◽  
Snail Species ◽  
Physa Acuta ◽  
Tarebia Granifera

An account is given of all invasive alien freshwater snail species samples found in the Kruger National Park currently on record in the National Freshwater Snail Collection(NFSC) database. This report mainly focuses on samples collected during surveys of selected water bodies in the Kruger National Park (KNP) during 1964, 1995, 2001 and 2006. The progress made by four alien invasive freshwater snail species, Lymnaea columella, Physa acuta, Aplexa marmorata and Tarebia granifera, in colonising water bodies since first being recorded in the KNP is addressed. The results clearly show that all four species are in the process of becoming more widespread than they were when first recorded. However, T. granifera is the only one of these species of which exceptionally dense populations were encountered in several water bodies. All indications are that this species could already have had a negative impact on the species diversity of molluscs in these water bodies, and it is recommended that the situation be closely monitored.

scholarly journals Herbaceous species diversity patterns across various treatments of herbivory and fire along the sodic zone of the Nkuhlu exclosures, Kruger National Park

Koedoe ◽  
2013 ◽  
Vol 55 (1) ◽  
Author(s):  
Helga Van Coller ◽  
Frances Siebert ◽  
Stefan J. Siebert
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Plant Species ◽  
Significant Variation ◽  
National Park ◽  
Plant Species Richness ◽  
Kruger National Park ◽  
Riparian Zones ◽  
Herbaceous Plant ◽  
Herbaceous Species

Understanding relationships between large herbivores and plant species diversity in dynamic riparian zones is critical to biodiversity conservation. The Nkuhlu exclosures in the Kruger National Park (KNP) provided opportunity to investigate spatial heterogeneity patterns within riparian zones, as well as how these patterns are affected by fire and herbivory. A monitoring project was initiated to answer questions about the dynamics of the herbaceous layer and was aimed at determining, (1) whether there exists meaningful variance in herbaceous plant species richness and diversity across different treatments in the ecologically sensitive sodic zone and (2) whether an increase in herbaceous biomass, an artefact of herbivory and fire exclusion, suppresses herbaceous plant species diversity and richness. Herbaceous vegetation was sampled in two 1 m2 circular sub-plots in the eastern and western corners of 81 fixed plots. The biomass of each plot was estimated with a disc pasture meter (DPM) diagonally with the plot. DPM-readings were converted to kg/ha, according to the latest conversions for the Lowveld Savanna. Species richness and biomass showed significant variance across treatments, whereas no significant variation in herbaceous species diversity was perceived. Combined treatment of fire absence and herbivore presence contributed to higher forb species richness in the sodic zone. Biomass is significantly higher in fully fenced areas where herbivores are excluded, as opposed to the open and partially fenced areas. Although no significant variation was recorded for diversity across treatments, lowest diversity was recorded in the absence of all herbivores, especially in combination with fire treatment. Therefore herbivores are essential in sustaining herbaceous plant species richness in the sodic zone, whilst no significant results were found with regard to their effect on species diversity. Although statistically non-significant, fire seems to suppress species richness.Conservation implications: This study could be used as framework to advance and develop science-based management strategies for, at least, the sodic zones of the KNP. Research in these exclosures will create better understanding of these landscapes, benefit ecosystem conservation planning of national parks and also provide valuable long-term information on key ecological processes.

scholarly journals Annotated and Updated Checklist of Land and Freshwater Molluscs from Asturias (Northern Spain) with Emphasis on Parasite Transmitters and Exotic Species

Diversity ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 415
Author(s):  
Omar Sánchez ◽  
Jairo Robla ◽  
Andrés Arias
Keyword(s):  
Exotic Species ◽  
Animal Health ◽  
Freshwater Snail ◽  
Parasitic Infections ◽  
Snail Species ◽  
Intermediate Hosts ◽  
Northern Spain ◽  
Current Increase ◽  
Freshwater Molluscs ◽  
Local Diversity

Land and freshwater molluscs are the most abundant non-arthropod invertebrates from inland habitats worldwide, playing important ecological roles and some being important pests in agriculture. However, despite their ecological, and even economic and sanitary importance, their local diversity in many European regions is not perfectly understood, with a particularly notableknowledge gap in the northern Iberian malacofauna. This work aims at providing a revised checklist of continental gastropods and bivalves from the Asturias (northern Spain), based on the examination of newly collected and deposited material and on the critical analysis of published and gray literature. A total of 165 molluscan species are recognized. Ten species constitute new records from Asturias and seven from northern Iberian Peninsula. Seventeen species are introduced or invasive, evidencing the current increase of the bioinvasion rate in continental molluscs. Furthermore, all these exotic species are parasite transmitters or trematode intermediate hosts, and thus represent a potential bio-sanitary risk for human and other animal health. The provided data strongly suggest that the increase of invasive freshwater snail species can lead to an increase in parasitic infections, and this is a crucial point that transcends the merely scientific to the political-social sphere.

scholarly journals Diversity of Land and Freshwater Snail (Mollusca: Gastropoda) of Laiwangi Wanggameti National Park, Sumba Island, Indonesia

2021 ◽  
Vol 6 (2) ◽  
pp. 162-173
Author(s):  
Nova Mujiono ◽  
Nur Rohmatin Isnaningsih
Keyword(s):  
Population Density ◽  
Species Composition ◽  
National Park ◽  
Dominant Species ◽  
New Records ◽  
Land Snail ◽  
Freshwater Snail ◽  
The Other ◽  
Snail Species ◽  
Number Of Species

A study on the malacofauna of Laiwangi Wanggameti National Park (LWNP) in Sumba Island has been conducted. This study aims were to reveal the diversity of malacofauna in Sumba and compare it with those in the Lesser Sunda Islands. Observations were made on 20 stations using plots (10 x 10 m) in Wanggameti and Laiwangi. Specimens were collected for two hours in each plot. Twenty families and 44 species have been identified. The overall number of species from Sumba increased from 126 to 143 species. The LWNP represents 31% diversity of malacofauna in Sumba Island. Seventeen species are considered as new records for the island. Five endemic land snail species are still observed inside the park. The diversity and population density tend to be higher in Laiwangi area with lower altitudes than in Wanggameti area with higher altitudes. Two dominant species are Asperitas bimaensis cochlostyloides and Tarebia granifera. Species composition in Sumba is more similar to Bali compared with the other six neighboring islands.

The freshwater molluscs of the Kruger National Park

Koedoe ◽  
1967 ◽  
Vol 10 (1) ◽  
Author(s):  
G. Oberholzer ◽  
J. A. Van Eeden
Keyword(s):  
National Park ◽  
Kruger National Park ◽  
Freshwater Molluscs

The freshwater molluscs of the Kruger National Park

scholarly journals The influence of fire on populations of small mammals of the Kruger National Park

Koedoe ◽  
1981 ◽  
Vol 24 (1) ◽  
Author(s):  
N. G Kern
Keyword(s):  
Species Diversity ◽  
Species Composition ◽  
Small Mammals ◽  
Small Mammal ◽  
National Park ◽  
Kruger National Park ◽  
Control Treatment ◽  
Mammal Species ◽  
Low Diversity ◽  
Small Mammal Species

A total of 16 000 trap-nights was employed over eleven months to examine the influence of burning on small mammal populations in two major veld-types of the Kruger National Park. Four burning treatments (control, annual August burning, triennial August and April burning) were examined in detail and the following parameters determined: small mammal species composition, population density, biomass and species diversity. The control treatment had a high, stable small mammal density, biomass and diversity; the annual burning treatment had a low diversity and was dominated by Tatera leucogaster. The triennial burning treatments showed a cycle of species composition from domination by T. leucogaster following burning, through domination by other rodent species to domination by Crocidura hirta at the end of the cycle. The distributions and movements of the small mammals can be explained in terms of cover and litter preferences.

Managing rivers for conservation and ecotourism in the Kruger National Park

1995 ◽  
Vol 32 (5-6) ◽  
pp. 227-233 ◽  
Author(s):  
F. J. Venter ◽  
A. R. Deacon
Keyword(s):  
National Park ◽  
Good Condition ◽  
Kruger National Park ◽  
Rapid Expansion ◽  
Natural Environments ◽  
The West ◽  
The Past ◽  
Management Actions ◽  
Flow Through ◽  
Three Rivers

Six major rivers flow through the Kruger National Park (KNP). All these rivers originate outside and to the west of the KNP and are highly utilized. They are crucially important for the conservation of the unique natural environments of the KNP. The human population growth in the Lowveld during the past two decades brought with it the rapid expansion of irrigation farming, exotic afforestation and land grazed by domestic stock, as well as the establishment of large towns, mines, dams and industries. Along with these developments came overgrazing, erosion, over-utilization and pollution of rivers, as well as clearing of indigenous forests from large areas outside the borders of the KNP. Over-utilization of the rivers which ultimately flow through the KNP poses one of the most serious challenges to the KNP's management. This paper gives the background to the development in the catchments and highlights the problems which these have caused for the KNP. Management actions which have been taken as well as their results are discussed and solutions to certain problems proposed. Three rivers, namely the Letaba, Olifants and Sabie are respectively described as examples of an over-utilized river, a polluted river and a river which is still in a fairly good condition.

Sign in / Sign up

Export Citation Format

Share Document